Recent research has clearly implicated marital conflict as a risk factor for children's development of mental health problems such as depression and conduct disorder. of particular concern are families where conflict has been elevated as a result of the parents' divorcing. Children in these families are expected to be exposed to more marital conflict and to exhibit greater mental health problems. Two questions of considerable importance for theory and clinical work will be explored with this research. First, what is the nature of differences in siblings' responses to their parents' marital conflict, where one child reacts strongly to the parents' conflict, whereas a sibling seems to be relatively unaffected? Second, how do different patterns of marital conflict influence the children's way of dealing with their own interpersonal conflicts? The goal of this research is to study children's sibling relationships and mental health in families where the parents have divorced in the past year in order to understand how qualities of the sibling relationship may provide a buffer, or may exacerbate the negative impact of their parents' conflict of primary interest is how siblings deal with interpersonal conflict and with strong negative emotions, such as anger and sadness. Fifty families with two children in middle childhood (7-11 years) will be recruited to participate in the research. In these families both children will be of the same gender in order that clear comparisons can be made with data already available from children whose parents have not divorced. The siblings will be assessed using multiple methods (interview, observation, self-report), and both parents will be asked to provide questionnaire data; only the primary residential parent will be interviewed. These data will add essential information to the limited knowledge we have about children's sibling relationships in middle childhood. This research is important because it will help us understand the links between marital conflict, sibling relationships, and individual adjustment. It is also noteworthy because of its emphasis on gender differences and their role in mental health problems.